Everyones maps are different all you can do is explore especially desert biomes.
I found mine after taking a different route to the HQ from Bills.

I HAVE BEEN LOOKING EVERYWHERE!
Also I think I found Kan's base location while looking

Worlds are tile based but the tiles are randomly placed then land fillers are added to merge into those main tiles.

Go somewhere different like a hill top and spam build wood blocks under your feet whilst constantly jumping.
This will give you height for a good view of surroundings.
When done, delete blocks.. Don't jump off.!

Look for red desert areas you haven't searched.

If not try a restart if your not to far progressed as a new world is created then.